1. Field
This disclosure generally relates to systems and methods for moving an object.
2. Description of Related Art
The inclined plane is one of the simplest fundamental mechanical devices, its use was employed in the construction of the pyramids. The advent of machine tools saw the introduction of screw threads and screw jacks with which a single man can lift a building. High precision worm gears exhibit tremendous mechanical advantage in a single pass. All of these had obvious limitations due to friction. The performance and speed of operation took a big step forward in recent years with the introduction of ball screws with recycling balls which greatly reduced sliding contact.
In the 1960's magnetic bearings were invented and developed (See Magnetic Bearings for Spacecraft, NASA/GSFC X 721-72-56 P.A. Studer, January 1972), providing not only near frictionless support but eliminating the need for lubrication which allows such systems to be employed in clean rooms, medical facilities, and food processing plants. The lack of physical contact can eliminate wear and allow lifetimes independent of speed.